title: Limb-girdle muscular dystrophy type 2I is not rare in Taiwan.
abstract: Alpha-dystroglycanopathy is caused by the glycosylation defects of α-dystroglycan (α-DG). The clinical spectrum ranges from severe congenital muscular dystrophy (CMD) to later-onset limb girdle muscular dystrophy (LGMD). Among all α-dystroglycanopathies, LGMD type 2I caused by FKRP mutations is most commonly seen in Europe but appears to be rare in Asia. We screened uncategorized 40 LGMD and 10 CMD patients by immunohistochemistry for α-DG and found 7 with reduced α-DG immunostaining. Immunoblotting with laminin overlay assay confirmed the impaired glycosylation of α-DG. Among them, five LGMD patients harbored FKRP mutations leading to the diagnosis of LGMD2I. One common mutation, c.948delC, was identified and cardiomyopathy was found to be very common in our cohort. Muscle images showed severe involvement of gluteal muscles and posterior compartment at both thigh and calf levels, which is helpful for the differential diagnosis. Due to the higher frequency of LGMD2I with cardiomyopathy in our series, the early introduction of mutation analysis of FKRP in undiagnosed Taiwanese LGMD patients is highly recommended.
authors.affiliation: Department of Pediatrics, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan.
authors.forename: Wen-Chen
authors.initials: WC
authors.lastname: Liang
authors.forename: Yukiko K
authors.initials: YK
authors.lastname: Hayashi
authors.forename: Megumu
authors.initials: M
authors.lastname: Ogawa
authors.forename: Chien-Hua
authors.initials: CH
authors.lastname: Wang
authors.forename: Wan-Ting
authors.initials: WT
authors.lastname: Huang
authors.forename: Ichizo
authors.initials: I
authors.lastname: Nishino
authors.forename: Yuh-Jyh
authors.initials: YJ
authors.lastname: Jong
mesh_terms: D000293:Adolescent; D000328:Adult; D009202:Cardiomyopathies / Q000209:etiology / Q000235:genetics; D002648:Child; D015331:Cohort Studies; D004252:DNA Mutational Analysis; D049030:Dystroglycans / Q000378:metabolism*; D005260:Female; D005786:Gene Expression Regulation / Q000235:genetics; D006801:Humans; D008297:Male; D018482:Muscle, Skeletal / Q000000981:diagnostic imaging / Q000473:pathology; D049288:Muscular Dystrophies, Limb-Girdle / Q000175:diagnosis / Q000453:epidemiology* / Q000378:metabolism; D010430:Pentosyltransferases; D011506:Proteins / Q000235:genetics; D011859:Radiography; D012189:Retrospective Studies; D013624:Taiwan / Q000453:epidemiology; D015898:Tomography Scanners, X-Ray Computed; D055815:Young Adult
chemical_list: D011506:Proteins; D049030:Dystroglycans; C443107:FKRP protein, human; D010430:Pentosyltransferases
keywords: Alpha-dystroglycan; Alpha-dystroglycanopathy; Dilated cardiomyopathy; FKRP; Glycosylation defect; Laminin binding; Limb-girdle muscular dystrophy type 2I; Muscle imaging